57 



the La Mota Mountain region of Trans-Pecos Texas. TEXAS JOURNAL 

 OF SCIENCE 5W: ^03-415. 



The geomorphology, topography, vegetation and climate of the area 

 are described in detail. 8 vegetational-topographical associations are 

 described, and the lizard species found in each are listed. Cnemido - 

 phorus inornatus is found only in the ocotillo-catclaw association of 

 mesa tops. _C. tesselatus is the most widespread species, occurring in 

 7 associations. The confusion over the type-locality of this species 

 is detailed, and is herein restricted to "Pueblo, Pueblo County, Colo- 

 rado: collected on the morning of 19 July 1820 near the mouth of Castle 

 Rock Creek (probably = Fountain Creek)." C. tigris marmoratus was col- 

 lected from ^- association. It was more numerous than C. tesselatus in 

 two of them and less numerous in the other two; about equal numbers of 

 the two species were collected in the i4- associations. Biogeographical 

 relationships are discussed. 



15*. — . 1957a. Observations on the natural history of ^ species of 

 whiptail lizard, Cnemidophorus (Sauria, Teiidae), in Trans-Pecos Texas. 

 SOUTHWESTERN NATURALIST 2(2-3): 105-121. 



Detailed observations on the ecological attributes of Cnemido - 

 phorus perplexus (= inornatus ), _C. sack! (probably = gularis ), _C. tes- 

 selatus and _C. tigris marmoratus were made in Brewster and Presidio 

 Counties, Texas. Foraging activities and behavioral differences are 

 described. Behavioral thermoregulation and microhabitat selection are 

 discussed in relation to seasonal ambient soil temperatures. Data on 

 home ranges are presented for _C. t. marmoratus . One lizard recaptured 

 17 times had a home range calculated as .53 acres, but this study only 

 encompassed H days, so this value may be imprecise. Lizards were not 

 territorial. Reproductive data is interpreted as indicating a single 

 long breeding season; however, the data also suggests that two clutches 

 per female are laid. The separation of adult and juvenile activity 

 patterns late in the year is discussed. 



155. — . 1957b. Some aspects of competition in natural populations 

 of whiptail lizards (genus Cnemidophorus) . TEXAS JOURNAL OF SCI- 

 ENCE 9(4): 410-4^^7. 



Several species (exsanguis, gularis , inornatus , tesselatus and 

 tigris ) were studied at 3 locations in Trans-Pecos Texas. Field time 

 of the investigator was limited. There appears to be distinct ecolo- 

 gical separation between all the species, with very little overlap. 

 One species always predominates when two occur together in the same 

 vegetation association, while the other is reduced in numbers. The 

 least amount of ecological separation appears to be between tigris and 

 tesselatus ; they are the only two species that occur together in the 

 same association. Populations of all the species are disjunct through- 



